The new synthetic methods involving organosulfur compounds include (1) the conversion of enones to furans and of vinylpyridines to indolizines, (2) the development of new annulation methods for cyclic enones, (3) the production of a variety of sulfur-bearing dienes, their utilization in Diels-Alder reactions, and the further elaboration of the resulting adducts, taking advantage of the great verstility of sulfur, (4) the use of the products of the reactions of aluminum thiophenoxide with alpha, beta-unsaturated esters and kerones for functional group transpositions and for the preparation of new sulfur-bearing dienes, (5) the synthetic exploitation and generalization of a new ring closure reaction of the dianions of bis-thioacetals, (6) the synthetic of a new cyclization reaction of the anions of 3-(phenylthio)thioacetals coupled with a conversion of the resulting cyclopropanone dithioketals to 1(phenylthio)cyclo-propyllithium reagents and generalization of this new anion-producing reaction to other sulfur-bearing functional groups.